Restoration of cheatgrass (Bromus tectorum) invaded rangelands is among the largest management challenges in the Intermountain West. In an effort to reduce the conversion of native sagebrush steppe into annual communities, the Bureau of Land Management reseeds rangelands after fire at very large scales, seeding tens of thousands of acres per year in extreme fire years. These seeding efforts have mixed success.

One factor that may affect the establishment of seeded species in invaded areas is the choice of seeds used in restoration.

We have demonstrated that plants vary in their ability to tolerate competition with cheatgrass, with traits such as seedling root to shoot ratio and the production of fine and coarse roots affecting the survival and performance of native grasses such as squirreltail (Elymus elymoides), big squirreltail (E. multisetus), and sandberg bluegrass (Poa secunda).

This research is comparing the relative performance of native grasses, collected from field sites close to the area to be restored, with commercially-available seeds.

Two types of native seeds will be grown in these experiments: a randomly selected pool of native plants, and a pool of plants that possess traits we have found to be particularly beneficial for surviving in invaded areas. Seeds will be planted in 5 field sites in four states, and survival and growth will be monitored for three growing seasons.

Additionally, seeds will be collected from surviving plants and compared with the original seeding mix to further determine which traits increase survival in invaded systems.

Finally, we will establish an increase garden at UNR for plants collected from Nevada, which will give us the ability to

test these seeds in realistic rangeland drill seedings in future projects and

share seeds with collaborators who may be interested in releasing these plants for use in the Great Basin.

Benefits to rangelands will be the potential for improvement of restoration of the most invaded of our Great Basin plant communities.

Cheatgrass (Bromus tectorum) invasion in the Great Basin is arguably the largest ongoing invasion in North America, converting large areas of naturally shrub, forb, and grass communities of the sagebrush steppe into annual communities dominated by cheatgrass and other disturbance-oriented species (Bradley and Mustard 2006). The invasion of cheatgrass increases fire return intervals in the Great Basin, which limits the ability of native species to resprout or recruit naturally into fire sites (Whisenant 1990, Link et al. 2006).

In an effort to slow the conversion of native steppe into annual communities, the Bureau of Land Management reseeds rangelands after fire at a very large scales, seeding million of acres in extreme fire years (BLM statistics). These efforts have mixed success, with the best fire recovery seen at sites where native resprout from the seedbank or from root crowns (Kulpa 2010, James 2011).

Multiple issues affect the recovery of seeded fires after burns. Factors such as yearly weather, seeding methods, and timing of seeding are certainly responsibly for observed successes and failures. Additionally, we suspect that the identity of seeds used in restoration affects the successful establishment of seeds in rangeland seedings in highly disturbed areas in general, and in Nevada rangelands specifically.

Ongoing work in Dr. Leger's lab suggests that seeds used in restorations do not represent optimal traits for growth in highly invaded systems of the Great Basin. Additionally, seeds currently available for use in the Great Basin are collected from areas on the northern or eastern areas of the floristic provence, with only one available cultivar released from a collection in Nevada (Jones and Larson 2005).

Many studies have illustrated the potential for plants to adapt to local conditions, and these adaptations have been observed to affect plant establishment in the wild (Clausen et al. 1940, Fenster and Galloway 2000, Joshi et al. 2001, Leimu and Fisher 2008). Thus, the lack of collections from Nevada, combined with competition from cheatgrass, may strongly affect the establishment of restoration seeding in Nevada in particular, and in invaded areas of the Great Basin in general.

By selecting seed sources from areas that match local abiotic and biotic conditions, and selecting specific plants that possess traits that make them perform well in cheatgrass-invaded systems, it may be possible to improve rangeland restoration in highly invaded areas. These seeds are not available to land managers at this time, and this project will provide evidence required for introducing adapted seeds into restoration seed production. Improving the success rate of post-fire seedings would benefit landowners, ranchers who graze public lands, state and federal agencies who use resources to restore invaded systems, wildlife, and native plant communities in the Intermountain West.

To study how phenotypic traits affect seedling establishment for two native perennial grasses of ecological and economic importance, and

To compare how well plants with a suite of desirable traits establish relative to plants from commercial sources.

Aarssen, L.W., B.S. Schamp, and J. Pither. 2006. Why are there so many small plants? Implications for species coexistence. Journal of Ecology 94: 569-580.

Aerts, R., and F. S. Chapin. 2000. The mineral nutrition of wild plants revisited: a re-evaluation of processes and patterns. Advances in Ecological Research 30: 1–67.